I wanted to move quickly as I was pursuing a few opportunities at the time and was trying to balance deadlines/dates across all of them. I had a short phone screen the Friday before Labor Day weekend, had an onsite 2 weeks later, and was extended an offer the next day. Including all negotiation about which team I was going to work on and other offer negotiations, it was less than 3 weeks from when my referral was passed to my friend's contact at Amazon to offer acceptance.